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51.
In brain tissue a spectrin-like calmodulin-binding protein calspectin, or fodrin, is concentrated in a synaptosome fraction, where most of the calspectin is associated with the synaptic membranes. This endogenous calspectin was phosphorylated by protein kinase system(s) associated with the membranes. Here, we report the solubilization and partial purification of the membrane-associated calspectin kinase activity. The activity was resolved on a gel filtration column into two fractions, peaks I and II having estimated Mr of 800 000 and 88 000. The activity of peak I was dependent on the presence of both Ca2+ and calmodulin. Peak II revealed a basal activity in the absence of Ca2+ and calmodulin, which was stimulated 2-fold by addition of Ca2+. Calmodulin had no effect on the peak II activity. 相似文献
52.
Michio Ohba Keiko Ono Keio Aizawa Setsuo Iwanami 《Journal of invertebrate pathology》1981,38(2):184-190
Bacteriological and serological characteristics of three Bacillus thuringiensis isolates obtained in Japan were investigated. They formed typical rhomboidal parasporal inclusions but flagellar (H) antigens of these isolates were different from those of the known 17 H serotypes of B. thuringiensis. The three isolates were divided into two new serotypes (serotypes 18 and 19). The serotype 18 isolate (3–71) produced thermostable exotoxin and the inclusions of this isolate were toxic to larvae of the silkworm, Bombyx mori, but nontoxic to larvae of the mosquito, Aedes aegypti. The other isolate (119-72) belonging to serotype 18 produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. However, other bacteriological properties of the isolate 119-72 were similar to those of the isolate 3–71. The serotype 19 isolate (117-72) produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. Acid production from saccharose and the production of brownish purple pigment were observed in the two serotype 18 isolates, while neither of them was observed in the serotype 19 isolate. In other 29 biochemical properties tested, there was no difference among the three isolates. Based on these characteristics, the following two subspecies names are proposed: Bacillus thuringiensis subsp. kumamotoensis (serotype 18) for the type strain 3–71 and Bacillus thuringiensis subsp. tochigiensis (serotype 19) for the type strain 117-72. 相似文献
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Experimental transfer of the lung stage worms of Angiostrongylus cantonensis was performed between permissive hosts (rats) and between permissive (rat) and nonpermissive hosts (guinea pigs and rabbits). These worms from rats were rejected when implanted into nonpermissive hosts. Unexpectedly, similar worms did not survive well even in permissive hosts; the majority of recipient rats did not have first-stage larvae (L1) in their stools and, even when positive for L1, the number of the larvae shed was few. These findings contrast with the successful pulmonary arterial transfer of younger, intracranial-stage worms. It was shown that differences in rat strain between donor and recipient had no significant effect on the subsequent worm survival in recipient hosts. The alteration of maintaining conditions of the intrapulmonary worms, prior to transfer, in terms of temperature, media, and maintaining period, also showed no profound effect on the subsequent worm survival. The kinetics of precipitating and reaginic antibody levels in rats implanted with the intrapulmonary worms were analogous to those in rats with intracranial-stage worms. The findings indicate that some qualitative differences may exist between the worms obtained from two different sites. 相似文献
55.
Kenji Katagiri Toshihiko Takeuchi Keiko Taniguchi Makoto Sasaki 《Analytical biochemistry》1978,86(1):159-165
Pancreatic elastase was isolated from acetone powder of porcine pancreas by a one step purification procedure on a trialanyl CH-Sepharose 4B affinity column. This column exhibited affinity not only for active elastase but also for trypsin and chymotrypsin which were present in the same pancreatic powder. However, as the extent of affinity toward elastase is considerably higher, the proper conditions were determined with which the adsorbed elastase was isolated in a highly purified form. The yield of elastolytic activity ranged from 60–85% and the purified elastase was shown to be one component by polyacrylamide disc electrophoresis. 相似文献
56.
Restriction endonucleases EcoRI and HindIII generated fragments of T4 cytosine-containing DNA were inserted into bacteriophage vector λgtSuIII and plasmid vectors pMB9 and pBR313. Resulting clones were screened for hybridization with 32P labeled T4 tRNA. Recombinant bacteriophages and plasmids were isolated which contained a T4 fragment coding for T4 RNA species 1 and 2 and T4 tRNAArg. Selected λ-T4 hybrid bacteriophages were grown to high titer and their DNA analyzed by gel electrophoresis. 相似文献
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59.
Maryse Bourgault Heidi A. Webber Karine Chenu Garry J. OLeary Thomas Gaiser Stefan Siebert Fernanda Dreccer Neil Huth Glenn J. Fitzgerald Michael Tausz Frank Ewert 《Global Change Biology》2020,26(7):4079-4093
Early vigour in wheat is a trait that has received attention for its benefits reducing evaporation from the soil surface early in the season. However, with the growth enhancement common to crops grown under elevated atmospheric CO2 concentrations (e[CO2]), there is a risk that too much early growth might deplete soil water and lead to more severe terminal drought stress in environments where production relies on stored soil water content. If this is the case, the incorporation of such a trait in wheat breeding programmes might have unintended negative consequences in the future, especially in dry years. We used selected data from cultivars with proven expression of high and low early vigour from the Australian Grains Free Air CO2 Enrichment (AGFACE) facility, and complemented this analysis with simulation results from two crop growth models which differ in the modelling of leaf area development and crop water use. Grain yield responses to e[CO2] were lower in the high early vigour group compared to the low early vigour group, and although these differences were not significant, they were corroborated by simulation model results. However, the simulated lower response with high early vigour lines was not caused by an earlier or greater depletion of soil water under e[CO2] and the mechanisms responsible appear to be related to an earlier saturation of the radiation intercepted. Whether this is the case in the field needs to be further investigated. In addition, there was some evidence that the timing of the drought stress during crop growth influenced the effect of e[CO2] regardless of the early vigour trait. There is a need for FACE investigations of the value of traits for drought adaptation to be conducted under more severe drought conditions and variable timing of drought stress, a risky but necessary endeavour. 相似文献
60.
Nayara F. C. Castro Luiz R. Falleiros‐Júnior Mariele I. Zuco Ana P. S. Perez Sebastio R. Taboga Fernanda C. A. Santos Patrícia S. L. Vilamaior 《Cell biology international》2020,44(7):1467-1480
Prenatal and neonatal exposure to estrogenic compounds, such as ethinylestradiol (EE), promotes a variety of developmental disorders, including malformations and alterations in the morphology of glands, such as the prostate gland. Therefore, the aim of this study was to evaluate the morphological effects of neonatal exposure to EE on prostatic tissue and on the identification and quantification of gerbil gland macrophages in adult and senile Mongolian gerbils. The animals were exposed to EE (10 μg/kg/day) and to the vehicle, mineral oil (100 μL) (control group) during the first 10 days of postnatal life (lactation period). Adult gerbils were euthanized at 120 days and senile gerbils at 12 months of age. Our findings permitted verification of the presence of areas with proliferative foci in the prostate glandular portions in the adult and senile animals exposed to EE. There was also an increase in macrophages in the prostate tissue of adult and senile gerbils; these cell types alter the stromal microenvironment and possibly modify the interactions between the epithelium and stroma. Neonatal exposure to EE changes the pattern of prostatic development, leading to alterations in the arrangement of cells, including macrophages, and may be related to the onset of proliferative disorders in the prostate of adult gerbils and during aging. 相似文献